Retrieve column definitions, data types, and constraints for one or more PostgreSQL tables. Provide table names and an optional schema to inspect table structure before writing queries.
Get table structure for single or multiple tables
| Name | Required | Description | Default |
|---|---|---|---|
| schema | No | Schema name (default: public) | |
| tables | Yes | Table name(s) (comma separated list) |
Changes observed during successful MCP inspections.
v0.1.3Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden, yet it says nothing about the tool being read-only, the return content (columns, types, constraints, keys?), or behavior for unknown/mixed-case tables. Only the mutation-free nature can be inferred from the verb 'Get'.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
A single front-loaded sentence with no filler. It is efficiently sized, though it is arguably too terse given the tool's moderately complex return behavior.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
No output schema exists, so the description should ideally clarify what 'structure' entails and whether results are per-table or aggregated. Parameters are fully covered by the schema, which keeps this at a minimum-viable level rather than a failing one.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so both the 'schema' default and the comma-separated 'tables' format are already documented in the schema. The description's 'single or multiple tables' lightly reinforces the multi-table capability but adds no syntax or format detail beyond it.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States a specific verb+resource ('Get table structure') that is immediately distinguishable from list_tables and list_schemas, which return names rather than structure. It does not, however, explicitly name the sibling it supersedes, so the differentiation is inferred rather than stated.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
There is no when-to-use guidance, no prerequisite (e.g., must be connected first), and no routing to alternatives such as list_tables or query. The agent must infer all usage conditions from the tool name and the sibling set.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.